The third way of using R in Power BI is to create an R Script visual. This is especially useful when we want to create a visual such as small multiples that is not available (yet) in the suite of standard or custom PBI visuals.
Image that we have a daily time-series for December 2015 for the profit and loss (P&L), and we want to show a trellis of bar charts; one chart for each region (Asia, EMEA and US) and one for a Volcker flag (which is either In or Out). So we want to show six charts in all. We also want to show a bar on each chart in a different colour for each of three clusters. Given a data frame named dataset with date, Region, Volcker, Cluster and P&L columns, we can create a this in R using the ggplot2 library with the following code.
Once we have written and tested this code in RStudio, we can create a R Script Visual. The RScript visual provides a dataframe (R’s equivalent of a table) named dataset. This contains a column for each of the fields in the Values well – in this case Region, Cluster, VolckerFlag, Date and P&L.
We can copy our R snippet into the bottom of the R Script Visual code window.
Once done we can see our chart in Power BI.